Vibration under acceleration starting around 30mph

[psyduck]

So I just started getting a pretty strong vibration throughout my truck a few days ago that only happens under acceleration. Vibrates from about 30-50 pretty violently. After doing some research it seems that it is either the u-joints or maybe some sort of ignition problem? When I let go of the accelerator the vibration stops but starts back up the moment I press the gas.

I have had issues with my rpms dropping a bit low in idle (500rpm), and sometimes dying when I lightly tap the accelerator to move a tiny bit.

I'm also hearing a clunking sometimes when shifting from R-D as well as a slight mechanical click or pop once I start driving which I believe to be something with the brakes.

Anyone able to help before I take it to a shop?

Edit: I guess I should add this is a 2WD.

 

[mtbtim]

You mentioned it could be u-joints, which it can. Have you checked your rear driveshaft joints? If not, push and pull on them to see if you detect any movement. If there's movement, the joint is bad. Also check for gross play in the splines of the slip yoke connection to the main driveshaft.

The clunking during shifting could be a sign of a broken transmission or engine mount. I'd check those as well.